Seaport security tightens after diving threat

Seaport security is tighter since warnings about possible terror attacks by divers.

From John ZarrellaCNN Miami Bureau

(CNN) --About a year ago Barbara Froelich received a request that prompted her to contact the FBI.

Froelich, who runs a dive shop in the Florida Keys, said a Pakistani man sent her an e-mail requesting to take an advanced diving course.

"He sent me a deposit for the course that was on a cashier's check," she said. "The check cleared, but the gentleman never showed for the course."

Froelich alerted the FBI, but it may never be known whether the mystery man posed a threat. And in the wake of a recent Coast Guard warning that terrorist divers carrying explosives might target ships, security at the nation's seaports is tightening.

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CNN's John Zarrella reports cruise ships are under constant surveillance by the U.S. Coast Guard after warnings they may be targeted (June 21)

No security is infallible, but cruise lines said they believe the umbrella of protective measures -- those they acknowledge and those they don't -- could avoid a repeat of tragedy.

"It's been defined as a credible threat," said Capt. James Watson of the U.S. Coast Guard. "And as we have sorted through all the different information, this one is something that we need to act on, and we are acting on it."

In Miami, one of the Coast Guard's biggest responsibilities is keeping cruise ships safe. Helicopters watch from the sky. Police boats and cutters man the water. They enforce a zero tolerance policy, allowing no access to the channel whenever cruise ships are docked.

For obvious reasons, many of the deterrent measures are kept secret. But authorities said highly trained police divers are in the water on a regular basis to check for anything suspicious in the shipping channel.

Cruise passengers also face more security checks.

Since the warning, cruise lines said they have further enhanced shipboard security above the waterline. The industry remembers the 1985 hijacking of the Italian liner Achille Lauro off Egypt.

In an industry video, every piece of passenger luggage is X-rayed. Passengers and crew members receive identification cards with corresponding pictures stored in a database.

"One hundred percent of every person that comes on board is screened, positively identified and tracked in our system while they're with us as a passenger or a crew member," said Michael Crye, president of the International Council of Cruise Lines